SOLUTION: the diagonal of a rectangle is 15 cm. long. If its length is 3 cm. longer than its width, find the perimeter of the rectangle

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Question 631464: the diagonal of a rectangle is 15 cm. long. If its length is 3 cm. longer than its width, find the perimeter of the rectangle
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

the diagonal of a rectangle is 15 cm. long. 

 length is 3 cm. longer than its width highlight%28x%29

Question states*** 

appying the Pythagorean Theorem

 x^2 + (x+3)^2 = 225

 x^2 + x^2 + 6x + 9 = 225

 x^2 + 3x - 108 = 0

factoring

 (x +12)(x-9) = 0

       x = 9cm, its width (throwing out negative solution for unit measure)

              length = 12cm  9%2B3

 P = 2*9cm + 2*12cm = 42cm